It took me less than 5 minutes to sign up for a NetZero dial-up Internet account. But after canceling that account, I spent a week trying in vain to reverse a charge that the service levied after my cancellation request.

I had to call NetZero a total of five times, holding for several minutes and then enduring long and fruitless conversations with company agents every time I called. According to the NetZero representatives that I spoke to, I needed to talk to a supervisor to arrange a credit, but none was ever available when I called. In the end, I gave up and let NetZero keep the money.

To evaluate how difficult canceling an online service can be, I signed up for and then canceled 32 accounts, each at a different site. About a third of the services in my sample made the seemingly simple goal of canceling very hard to achieve (see the "Big Hassle" entries in "Want to Cancel That Service?").

Not all of my experiences were negative. Services such as a monthly New York Times TimesSelect online subscription and a monthly Consumer Reports Online account took only minutes to cancel and without lingering strings. But some others made me feel as though I'd joined the Sopranos' family business: Once I signed up, there was no quitting!